import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.Scanner;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class TcpEchoServer {
    private ServerSocket serverSocket = null;
    public TcpEchoServer(int prot) throws IOException {
        serverSocket = new ServerSocket(prot);
    }
    public void start() throws IOException {
        System.out.println("服务器启动");
        while (true){
            Socket clientSocket = serverSocket.accept();
            /*Thread t = new Thread(()->{
                processConnetion(clientSocket);
            });
            t.start();*/
            ExecutorService pool = Executors.newCachedThreadPool();
            pool.submit(new Runnable() {
                @Override
                public void run() {
                    processConnetion(clientSocket);
                }
            });
        }
    }

    private void processConnetion(Socket clientSocket) {
        System.out.printf("[%s:%d]客户端上线!",clientSocket.getInetAddress(),clientSocket.getPort());
        try(InputStream inputStream = clientSocket.getInputStream();
            OutputStream outputStream = clientSocket.getOutputStream()) {
            while(true){
                Scanner scanner = new Scanner(inputStream);
                if (!scanner.hasNext()) {
                    System.out.printf("[%s,%d]客户端下线",clientSocket.getInetAddress(),clientSocket.getPort());
                    break;
                }
                String request = scanner.next();
                String response = process(request);

                PrintWriter printWriter = new PrintWriter(outputStream);
                printWriter.println(response);
                printWriter.flush();

                System.out.printf("[%s,$d] req:%s,resp:%s\n",clientSocket.getInetAddress(),clientSocket.getPort(),request,response);
            }
        } catch (IOException e) {
            throw new RuntimeException(e);
        }finally {
            try {
                clientSocket.close();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
    }

    public String process(String request) {
        return  request;
    }

    public static void main(String[] args) throws IOException {
        TcpEchoServer server = new TcpEchoServer(9090);
        server.start();
    }
}
